This invention relates to truck ladders which facilitate the user's access to a truck bed; in particular, the invention relates to a detachable ladder for accessing the bed of a flatbed truck or trailer from the ground. In most cases, the bed of a flatbed truck trailer is about five feet above the ground surface, making it difficult to climb on and off the bed. It is frequently necessary to access the bed of a truck trailer while loading and unloading the trailer, and some trucks have permanently mounted step rails positioned for this purpose. However, a permanently mounted step rail must be mounted so as not to increase the overall width of the trailer in order to comply with highway regulations, and therefore such step rails are usually positioned vertically beneath the outer edge of the truck frame, which makes it difficult to use them for climbing onto the bed.
For safe operation and convenient ease of access, it is desirable that an access ladder be positioned at a reasonable angle relative to vertical, and it is also desirable that the ladder have some form of handrail to assist the user while climbing on the ladder. Furthermore, it is desirable that the ladder be portable so that it can be used at many points around the trailer bed, for frequently the trailer has a partial load which prevents access to the trailer bed where the partial load is located. It is also desirable that the ladder be capable of convenient stowage when not in use, but in a position which maintains a fixed attachment to the trailer so that the ladder cannot be lost while the truck is being moved. When the ladder is stowed it must be secured to prevent it from falling off the trailer, which could cause a dangerous highway hazard.